1. Field of the Invention
The present invention relates to a wiring structure of a loudspeaker with conductors mounted on the damper for the connection to the voice coil, and particularly to such a wiring structure having an improved coupling means between the end portion of the conductor at the outer peripheral portion of the damper and an input terminal mounted on the speaker frame.
2. Related Background Art
Conventional loudspeaker wiring structures are shown in FIGS. 1, 2A and 2B. A damper 1 for holding a voice coil 5 at the midpoint of a magnetic gap 6 is generally made of woven fabric, unwoven fabric or the like which is molded in a predetermined form after impregnating therein thermosetting rein such as phenol resin and forming thereon corrugations 11 of concentric circles. An electrical path for input signals to the voice coil 5 is established as in the following. Namely, conductors 2 such as copper foil are attached with adhesive agent or the like on the front or back surface of the damper 1. The lead 51 of the conductor 2 on the inner periphery side of the damper is connected to the voice coil 5, whereas the outer end portion 21 of the conductor 2 is connected to an input terminal 4 mounted on the speaker frame 7.
In the wiring structure shown in FIG. 1, the end 21 of the conductor 2 extends beyond the damper outer periphery 12, the end being maintained in a free state. The end 23 of this free portion 22 is coupled to the end portion 31 of a lug 3 of the input terminal 4 by means of solder H. Another coupling structure between the end portion 21 of the conductor 2 and the input terminal 4 is shown in FIGS. 2A and 2B. In this structure, the end 21 of the conductor 2 is flush with the damper outer periphery such that the end portion 31 of the lug 3 is coupled to the end 21 of the conductor by means of solder H as shown in FIG. 2B.
With the structure shown in FIG. 1, in connecting the end portion 31 of the lug 3 to the end of the free portion 22 extending from the end 21 of the conductor 2, it is necessary first to fix the end of the free portion 22 to the end portion 31 of the lug 3, and then solder them together. It is thus very difficult to realize an automatic operation of such soldering.
With the structure shown in FIGS. 2A and 2B, it is also difficult to stably make the end 21 of the conductor which is in flush with the outer periphery 12 of the damper, in contact with the lug 3, because the outer periphery 12 has essentially the nature of being warped. It is thus difficult to ensure an automatic soldering.
Further, the cut section 12a of the insulating fabric is present, as shown in the enlarged view of FIG. 2B, between the two soldered points of the conductor 2 mounted on the damper 1 and the end 31 of the lug 3 below the damper position. Therefore, such soldering may often result in a so-called "heap soldering" with considerably poor coupling stability, to thus unable to improve the product quality.
Furthermore, with the conventional wiring structures using the lug 3, the number of necessary components as described above is large, resulting in a difficulty of product cost reduction.